Core 3, the immunology/pathology core, provides services to all nine projects. It offers histologic support, qualitative pathologic interpretation and quantitative morphometric assessment of human and animal lung tissues, cell differentials from bronchoalveolar lavage and immunohistochemical analyses of lung neuropeptides. These services are provided under the supervision of a pulmonary pathologist and a pulmonary anatomist. A variety of immunological analyses are also offered. Class- specific immunoglobulin and antigen-specific antibody levels are available for human and rabbit sera. The core also provides rabbits which are preferentially synthesizing IgE antibodies and are bronchially hyperresponsive as a result of a series of antigen challenges via the airways. Lymphocyte-related immunological assays include lymphocyte separation, antigen- and mitogen-induced cytokine production (with storage of supernatants), and lymphocyte preservation for future phenotyping. Appropriate networks are in place to coordinate the handling of these samples for optimum utilization. A similar network is in place for the attainment of fresh human lung tissues. Cost savings arise from efficient networks (of plans and people working together) to ensure each portion of a sample is appropriately treated, assayed and/or transported as required. More importantly, the core provides centralized processing, analyzing and, when called for interpreting, tissues, BALs and blood samples, which means that results from various projects can be compared one with another.